Role of subsurface layer temperature inversion in cyclone induced warming in the northern Bay of Bengal

Abstract

Subsurface Layer Temperature Inversion (SLTI) is a prominent physical process occurring in the Bay of Bengal (BoB) during winter. BoB also witnesses intense cyclones during winter (post-monsoon). Sidr is a category-5 cyclone that occurred in the BoB during 11–15 November 2007. The present study emphasises bringing out the effect of SLTI on SST warming. This paper uses observations and modelling to present SLTI's role in surface layer post-cyclone warming. In the absence of SLTI, the cyclone induces surface cooling. However, in the case of a surface layer with SLTI, instead of cooling, sea surface warming of < 0.5 °C is observed near the head bay, where SLTI is prominent. Model results and observations suggest the role of entrainment and warming of the surface layer.